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Revenue Accounting for Contracts / Accounting for Joint Ventures (Pass-Through Costs Included in Revenues) (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
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Jun. 30, 2017 | Jul. 01, 2016 | Jun. 30, 2017 | Jul. 01, 2016
Revenue Accounting For Contracts Accounting For Joint Ventures [Abstract] |  |  |  |
Pass-through costs included in revenues | $ 628,070 | $ 616,160 | $ 1,861,615 | $ 1,887,620

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- Definition Revenue Accounting for Contracts / Accounting for Joint Ventures [Abstract] + References No definition available. + Details
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